Hydraulically damped rubber bearing that supports a mechanical subassembly

Claim 1

Control apparatus for a hydraulically damped rubber bearing adapted to support a vibrating mechanical subassembly on a substructure, said rubber bearing having a fluid-filled chamber and an actuator with an electromagnetic drive mechanism, associated with the fluid-filled chamber, for varying the hydraulic pressure in the chamber, said control apparatus comprising, in combination: (a) first signal emitter means coupled to the subassembly for sensing relative movement thereof and producing a signal representing such movement; (b) signal generator means coupled to the first signal emitter means for producing two harmonic-mutually phase shifted first signals having a common frequency equal to the frequency of vibration of the subassembly and producing a second signal that reproduces such common frequency in a characteristic manner; (c) a plurality of characteristic curve-generating means, each responsive to said second signal, for producing an output signal having a prescribed relationship to said second signal; (d) a plurality of first multiplier means, responsive to said first signals and said output signals, for producing third signals each representing the product of the respective values represented by one of said first signals and at least one of said output signals; (e) at least one first adding means, each coupled to receive two of said third signals, for producing a pair added signal representing the sum of the respective values represented by said pair of third signals; (f) second signal emitter means coupled to the substructure for sensing relative movement thereof and producing a fourth signal representing such movement; (g) a plurality of second multiplier means, responsive to said pair added signals and to said fourth signal, for producing fifth signals each representing the product of the respective values represented by one of said third signals and said fourth signal; (h) a plurality of transfer component means, each responsive to one of said fifth signals, for producing a sixth signal in dependence thereon, said transfer component means each having a transfer function which exhibits a low pass filter behavior above a prescribed frequency; (i) a plurality of third multiplier means, each responsive to one of said sixth signals and to one of said first signals, for producing a seventh signal representing the product of the respective values represented by one of said sixth signals and one of said first signals; (j) second adding means, responsive to said seventh signals, for producing an eighth signal representing the sum of the respective values represented by said seventh signals; and (k) power amplifier means, responsive to said eighth signal, for producing a power output signal for controlling said drive mechanism of said rubber bearing.