A mounting arrangement for a vehicle engine

Claim 1

I . A mounting arrangement for a vehicle engine of the kind comprising means (13) for mounting the engine (11) of the vehicle to the body (10) of the vehicle, which mounting means comprises a first fluid-tight chamber (18) of variable volume which contains fluid and which is arranged between the engine and the body so that the weight of the engine tends to reduce the volume of the chamber, means (14) for supporting the body on the suspension system (12) of the vehicle, which supporting means includes a second fluid-tight chamber (23) of variable volume, which chamber contains fluid and is arranged so that the load of the body on the suspension system tends to reduce the volume of the chamber, and a fluid communication (24) between the first and second chambers, characterised in that the fluid is a gas and relative movement between the engine (11) an body (10) or between the body (10) and suspension system (12) alters the pressure of the gas in one of the chambers (18, 23), which change in gas pressure is communicated to the other of the chambers (18, 23), the arrangement acting to tend to bring into phase the vibrational movements of the body and engine, the effective pressurised areas (as herein defined) of the mounting means (13) and supporting means (14) being approximately equal and the natural frequency of vibration of the body on the supporting means without the second chamber being approximately equal to the natural frequency of vibration of the engine on the effective gas spring (as herein defined).