Abstract: Disclosed is a device for measuring the rotational speed of a diesel engine. The device comprises a sensor element of electrostrictive effect type adapted to be detachably mounted on a delivery pipe of a fuel injection system of the diesel engine and having an intrinsic resonance frequency between 100 KHz and 10 MHz. A high frequency electric signal is transmitted from the sensor element in response to a high frequency oscillation generated in the fuel within the delivery pipe when fuel is injected. The device further comprises an amplifier, a converter, a wave shaping circuit, an integral circuit and an indicator. The high frequency electric signal is processed in the device and the rotational speed of the diesel engine is indicated by the indicator.
Type:
Grant
Filed:
August 23, 1978
Date of Patent:
November 13, 1979
Assignees:
C. Itoh & Co. Ltd., Okuda Koki Co., Ltd.