| 摘要 |
PURPOSE:To reduce actuation noise in an injector equipped with a laminated piezo-electric ceramics as a driving source by breaking pulse electricity to the ceramics temporarily and/or by applying pulse electricity temporarily after pulse has been broken. CONSTITUTION:When pulse electricity is applied to a laminated piezo-electric ceramics 18, the spreading of a lever 19 in a form of an S like configuration in cross section due to elongation to the direction of lamination causes a tension member 20 in a belt form to change its circular form into a straight line for opening a fuel injection hole 11 with a valve body 10 lifted so as to inject fuel. In an injection valve of a structure as described above, the ceramics 18 is energized in such a way that after it is energized for a period of tau1 for the pulse width tau0 of a pulse wave form corresponding to the quantity of fuel feed, it is de-energized for a period of tau2 to deaden inertia of the valve body 10, and it is energized later on for a period of tau3 for injection the predetermined quantity of fuel from the injection hole 11. And after an off-condition has been kept for a period of tau4, pulse electricity is applied temporarily for a period of tau5 for deadening inertia of the valve body 10. |
