| 摘要 |
PURPOSE:To detect the state of the piston ring speedily, easily, and accurately by projecting an ultrasonic wave on the abutment gap of the piston ring from a scavenging port and receiving a reflected wave from the piston groove surface or ring surface of the abutment gap. CONSTITUTION:The ultrasonic wave is projected on the ring abutment gap 11 of the piston ring 7 from an ultrasonic wave transmitter 100 through the scavenging port provided to the cylinder liner 2 of a two-cycle diesel engine. At this time, when the abutment gap 11 passes the scavenging port 10, the ultrasonic wave is incident on the surface of the piston groove 1a in the abutment gap 11 and reflected to enter an ultrasonic wave receiver 101. When a part other than the abutment gap 11 passes the scavenging port 10, the ultrasonic wave from the transmitter 100 is incident on a part other than the abutment gap 11 and reflected to enter the receiver 101. A measured distance is difference between the former and latter cases and this difference is used to detect whether or not the ring 7 is abnormal. |
