System for emergency lubrication and cooling of a mechanical stepup/stepdown gearing of the 'transmission box' type for a helicopter in the event of failure of the lubrication circuit

摘要

The system for emergency lubrication and cooling of a mechanical stepup/stepdown gearing assembly, particularly of the helicopter "transmission-box" type, acts in the event of failure of the lubricating circuit or of the devices for cooling the lubricating fluid (lubricant). It includes a device for injecting a liquid with a high latent heat of vaporisation, which may or may not be mixed with a lubricant product miscible with the said coolant liquid, and the injection device comes into play above and beyond a pre-established threshold value representing the non-functioning of the lubrication circuits and/or of the devices for cooling the lubrication fluid. The injection device operates by means of a specific circuit, that is to say one which is independent of the lubrication circuits. Main application: metal stepdown/stepup gearing - helicopters. IMAGE