Strain-wave (harmonic) gear
Harmonic Drive CSF-2A component sets
Harmonic Drive's general-purpose cup-type strain wave gear component set. It covers sizes from tiny instrument gears to very large robot-joint units, with zero backlash.
Key specifications
| Rated torque (max) | 3,550 Nm |
|---|---|
| Peak torque (max) | 15,500 Nm |
| Ratio | 30–160:1 |
| Backlash (max) | 0 arcmin |
| Sizes | 8, 11, 14, 17, 20, 25, 32, 40, 45, 50, 58, 65, 80, 90, 100 |
Summarised in our own words from Harmonic Drive SE / Harmonic Drive LLC's published data; series maxima, individual models vary. Last checked 2026-10-29. Source 1 · Source 2
Notes on this data
Torques are for CSF-100-160 (Harmonic Drive LLC). Rated (L10) is 3550 Nm, repeated peak 9180 Nm and momentary peak 15500 Nm (the momentary peak is stored in torque_Nm_peak_max). The smallest rating is CSF-8-30 at 0.9 Nm rated. Backlash is stated only as 'zero backlash'; standard accuracy is 1–2 arcmin. Ratio 30 is offered only on sizes 8–32. The page gives no input speed or bore. Variants include CSF-2A-LW, -2XH, -1U, -2UH, -2UP, -ULW and -GH.
Specify Motion is not affiliated with Harmonic Drive SE / Harmonic Drive LLC. Harmonic Drive and CSF-2A component sets are used only to identify the product. Comparisons use published figures; always confirm against the current datasheet.
Typical applications
Alternatives that meet or exceed these figures
Engineers often come to us with a Harmonic Drive part number and leave with an alternative that is easier to source, quicker to deliver or a better fit for the machine. These 3 series from our supply network are the closest match on published figures.
Cup-type strain-wave gear component sets for building your own joint; the LCSG high-torque version lifts capacity by around 30% over the standard LCS.
| Published maximum | CSF-2A component sets | LCS / LCSG |
|---|---|---|
| Rated torque | 3,550 Nm | — |
| Peak torque | 15,500 Nm | — |
| Ratio (max) | 160:1 | 500:1 meets or exceeds |
| Backlash (lower is better) | 0 arcmin | — |
Hollow-shaft strain-wave gear units with a large central bore for routing cables and services; LHSG is the high-torque version (over 30% more torque).
| Published maximum | CSF-2A component sets | LHS / LHSG |
|---|---|---|
| Rated torque | 3,550 Nm | — |
| Peak torque | 15,500 Nm | — |
| Ratio (max) | 160:1 | 500:1 meets or exceeds |
| Backlash (lower is better) | 0 arcmin | — |
Ultra-flat cup-type strain-wave gear with a very short axial length, light weight and high stiffness for its size.
| Published maximum | CSF-2A component sets | LCD |
|---|---|---|
| Rated torque | 3,550 Nm | — |
| Peak torque | 15,500 Nm | — |
| Ratio (max) | 160:1 | 500:1 meets or exceeds |
| Backlash (lower is better) | 0 arcmin | — |
Figures are the highest published for each series and are not always measured the same way. A higher figure is not automatically a better choice: mounting, duty cycle, feedback, connectors and approvals matter too. An engineer will check the fit against your application before recommending anything.
Other strain-wave (harmonic) gear series
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