초록 ▼

A generic technique for the detection of air-fuel ratio or torque imbalances in a three-cylinder engine equipped with either a current production oxygen sensor or a wide-range A/F sensor, or a crankshaft torque sensor, is disclosed. The method is based on a frequency-domain characterization of patte

A generic technique for the detection of air-fuel ratio or torque imbalances in a three-cylinder engine equipped with either a current production oxygen sensor or a wide-range A/F sensor, or a crankshaft torque sensor, is disclosed. The method is based on a frequency-domain characterization of pattern of imbalances and its geometric decomposition into two basic templates. Once the contribution of each basic template to the overall imbalances is computed, templates of same magnitude of imbalances but of opposite direction are imposed to restore air-fuel ratio (or torque) balance among cylinders. At any desired operating condition, elimination of imbalances is achieved within few engine cycles. The method is applicable to current and future engine technologies with variable valve-actuation, fuel injectors and/or individual spark control.

대표청구항 ▼

A generic technique for the detection of air-fuel ratio or torque imbalances in a three-cylinder engine equipped with either a current production oxygen sensor or a wide-range A/F sensor, or a crankshaft torque sensor, is disclosed. The method is based on a frequency-domain characterization of patte

A generic technique for the detection of air-fuel ratio or torque imbalances in a three-cylinder engine equipped with either a current production oxygen sensor or a wide-range A/F sensor, or a crankshaft torque sensor, is disclosed. The method is based on a frequency-domain characterization of pattern of imbalances and its geometric decomposition into two basic templates. Once the contribution of each basic template to the overall imbalances is computed, templates of same magnitude of imbalances but of opposite direction are imposed to restore air-fuel ratio (or torque) balance among cylinders. At any desired operating condition, elimination of imbalances is achieved within few engine cycles. The method is applicable to current and future engine technologies with variable valve-actuation, fuel injectors and/or individual spark control. laim 31 wherein said casing is formed from a metal material whose greatest component, by weight, is zinc. 37. The kit of claim 31 wherein said liner and said casing are made of the same material. 38. The kit of claim 31 wherein said liner is a casting. 39. A method of manufacturing a shaped charge liner for use with a casing for containing an explosive charge, the liner permitting a perforating jet to be formed therefrom upon detonation of the explosive charge, the casing having an apex at which to contact a detonation source, a mouth, and a divergent wall structure extending between said apex and the mouth, the divergent wall structure being narrower at said apex of said casing than at the mouth, said method comprising the steps of: forming said liner to have a central region and a divergent skirt extending from the central region; said skirt being mountable to the divergent wall structure to form a charge cavity between said liner and the casing for containing the explosive charge; said skirt being closer to the mouth than to the apex, and said central region lying closer to the apex than to the mouth upon mounting of said skirt to the divergent wall structure; and said liner for forming the perforating jet being formed from a metal material whose greatest component, by weight, is zinc. 40. The method of claim 39 wherein said step of forming said liner includes the step of providing a liner material that is predominantly zinc. 41. The method of claim 39 wherein said step of forming said liner includes the step of providing a liner material that is more than 70% zinc by weight. 42. The method of claim 39 wherein said step of forming said liner includes the step of providing a liner material that is more than 90% zinc by weight. 43. The method of claim 39 wherein said step of forming said liner includ