Patent ID: 6073601
Filing Date: 2000-06-13
Classification: F02B,Y02T

Abstract:
Air intake manifold for a fuel-injected internal combustion engine, said engine of the type comprising a plurality of combustion chambers, and comprising for each combustion chamber, an air duct, a downstream part of which comprises a single length of tube connected to at least one flange for attaching to a cylinder head of the engine, and an upstream part of which comprises two lengths of tube, namely a short upstream length and a long upstream length, each of which is fed with air via an upstream inlet from means for controlling the flow rate of inlet air, optionally a throttle body, a downstream outlet of each length of upstream tube being intended to be placed in communication with the upstream inlet of the single length of downstream tube via an element mounted between the upstream part and downstream part of each air duct, and through which there passes an acoustic bore, said element being able to move between two extreme positions, in one of which said element closes said short upstream length of tube while its acoustic bore connects said long upstream length of tube to said downstream length of tube, whereas in the other extreme position, said element closes said long upstream-length of tube while its acoustic bore connects said short upstream length of tube to said downstream length of tube, wherein said element is a retractable element, housed and mounted to pivot in a housing, and includes, perpendicular to its axis (A) of pivoting, two lateral faces each of which slides without rubbing contact over a respective one of two lateral faces of the housing when said retractable element pivots in said housing, thereby producing a good lateral seal between the element and the housing;wherein said retractable element comprises a hub pivotally attached to an operating spindle for pivoting the retractable element from one of the two extreme positions to the other; andwherein said operating spindle rotates about said pivot axis (A), said pivot axis being offset with respect to said acoustic bore.