Fixed-axis compound-train kinematics
Documented Compound Gear-Train Ratio Calculator
Calculate ratio magnitude, speed and rotation direction for a sequential parallel-shaft compound train. Optional power and torque results require a documented total train efficiency; no efficiency is assumed.
Kinematic result
Implemented kinematics
i=Πiⱼ
|nout/nin|=1/i
Each external mesh reverses rotation; each internal mesh preserves it. Direction is therefore based on the number of external meshes. The product rule applies only to the declared sequential compound arrangement.
Optional power and torque
Tin=Pin/ωin
Pout=ηtotal Pin
ωout=ωin/i
Tout=Pout/ωout=Tin·i·ηtotal
The page never supplies η. Enter a total efficiency documented for the actual operating point; a per-mesh catalogue estimate is not silently exponentiated. Power/torque output is unavailable at zero speed.
Sources and classification
KHK Gear Technical Reference defines reference diameter from tooth count and module and documents gear transmission-ratio relationships. The NASA gear-mesh technical memorandum uses the tooth-count/speed equality for a fixed gear mesh. OpenStax University Physics, section 10.8 gives rotational power P=τω; section 10.1 defines angular speed and RPM conversion.
This is a general kinematic and power-balance calculation, not a formula claimed from ISO. It does not implement ISO 6336 gear load capacity, ISO 1328 accuracy, or a conformity decision.
Why former guidance was removed
The former page assumed 97% efficiency per stage, called broad spur/helical/worm ratio ranges typical, accepted fractional tooth counts and showed opposite rotation for every first mesh. Those statements were not tied to the entered gear geometry, duty or manufacturer data. Defaults and presets also produced an immediate apparently operational result. They were removed.
Nikolai Shelkovenko
Nikolai Shelkovenko is a vibration analysis engineer and the founder and CEO of Vibromera. For more than 15 years he has balanced rotating equipment in the field rather than on a test bench: mulchers, industrial fans, crushers, centrifuges, shafts and spindles. That work is what the Balanset instruments grew out of — they were designed as a tool a specialist can carry to the machine and use alone, on site, not as laboratory equipment. Vibromera was founded in 2017 and has been based in Porto, Portugal, since 2023. Development, assembly and support of the Balanset line all happen here. The flagship instrument is the Balanset-1A, a portable analyser for single- and two-plane balancing and for vibration diagnostics. Nikolai is personally involved in customer support, in working through difficult balancing cases and in the development of the software. He works with customers worldwide, in any language.
