Diagnostic device for fuel injection valve of diesel engine

Abstract

Abstract PURPOSE:To enable reliable and easy diagnosis of the dynamic operating condition, during engine drive, of a fuel injection valve, by outputting only the signal, on a specified frequency band, of detection signals from a vibration sensor, and simultaneously said signal displaying and an output signal, provided when a fuel injection valve is in a normal condition. CONSTITUTION:A vibration sensor 4 generates a charge according to vibration of a fuel injection system, and outputs the charge, converted into a detected signal S1, to a charge amplifier 5. The amplifier 5 converts the detected signal S1 from the vibration sensor 4 into a voltage signal S2 to output it to a filter amplifier 6. The amplifier 6 extracts the signal, on a specified frequency band, of the voltage signals S2 from the amplifier 5, and the output signal is amplified by an operational amplifier OP2and an inversion amplifier to output the detected signal S3 to a synchroscope 7 serving as a display device. The scope 7 displays the detected signal S3 on a CRT picture, whereby the actually detected signal S3 and the normal detection signal S3 are simultaneously displayed on the CRT picture. Comparison of the waveforms thereof with each other permits easy discrimination of normal operation, during engine drive, of an injection valve.

Inventors

• 👤 Mitsuhiko Ezoe
• 👤 江副　光彦
• 👤 「よし」岡　茂樹
• 👤 Shigeki Yoshioka

Bibliographic Details