From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Series of questions regarding the operation and effects of a harmonic balancer.
| Identifier | ExFiles\Box 25\3\ Scan195 | |
| Date | 16th December 1926 guessed | |
| RE. HARMONIC BALANCER. (1) Assuming that a case of resonance exists within the working speed range of the crankshaft without the balancer, will the addition of this balancer completely eliminate the vibration at this speed? (2) If so, is it found that the previous vibration is divided into two parts - one occurring at a lower, and the other at a higher speed which would probably be outside the speed range? (3) If a lower speed vibration results, is it of sufficiently small amplitude to be negligible - in practice? (4) In an ordinary 6-cyl. engine without any attached form of damper, we have found that vibrations are present - and of appreciable magnitude - at speeds of 1/2, 1/3, 1/4 etc. of the main resonant speed, but not so severe as the main vibration. With the harmonic balancer fitted, are any of these lower vibrations present? (5) Is there any specific REASON why the damper should be fitted to a throw of the crankshaft instead of being fitted at the front end of the crankshaft as in the Lanchester?---------- | ||