Patent ID: 6814548
Filing Date: 2004-11-09
Classification: F04B

Abstract:
A multi-piston engine, comprising a drive shaft; at least two cylinders and pistons, the pistons being selectively driven by the alternating motion of the drive shaft and being respectively housed in the cylinders in order to delimit, for a fluid put in motion by the engine, a corresponding number of chambers with variable volume, each of which presents a predetermined maximum volume to the fluid and has a low pressure intake and a high-pressure outlet; and a corresponding number of delivery channels connecting the high pressure outlets of the respective chambers to the delivery outlet of the engine, each delivery channel having a predetermined cross section and a predetermined length, the movement of each piston bringing about a vibrational excitation of the engine, of determined fundamental frequency, and each chamber, in association with the piston which delimits the chamber and with the delivery channel which connects the chamber to the delivery outlet, forming a corresponding module of the engine, the engine further comprising at least a first spectral spreading means associated with a first pair of modules including a first pair of pistons, the first spectral spreading means being suitable for introducing, between the fundamental frequencies of the vibrational excitations resulting from the respective movements of the pistons of the first pair, a frequency shift (&Dgr;Fab) equal to at most 10% of the fundamental frequency of the vibrational excitation resulting from the movement of either of the pistons of the first pair.