The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 20, 1995
Filed:
Jan. 19, 1994
Motonobu Akaki, Aichi, JP;
Yasutoshi Yamada, Aichi, JP;
Nobuyuki Oota, Aichi, JP;
Masaki Mitsuyasu, Shizuoka, JP;
Daisaku Sawada, Shizuoka, JP;
Aisin Seiki Kabushiki Kaisha, Kariya, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
Piezoelectric element used in a fuel injection value is to be improved in its response to expansion and contraction, while the supply of an excess energy to the piezoelectric element is to be controlled. In a fuel injection control device in which an output voltage of the dc-dc converter is applied to a piezoelectric element via a choke coil and a thyristor, a current detection unit is provided between the dc-dc converter and the thyristor. A measured value of the electric charge, as found by integrating a charging current flowing through the current detection unit is compared by a comparator to a command value of electrical charges as found by processing the dc-dc converter output voltage. The results of comparison are supplied to a latch unit so as to be latched at the timing of a peak value of the charging current. A capacitor is charged and discharged depending on an output of the latch unit, and the terminal voltage across the capacitor and the output voltage of the dc-dc converter are compared to each other for controlling the output voltage of the dc-dc converter.