公开(公告)号：US3908167A

公开(公告)日：1975-09-23

申请号：US47644474

申请日：1974-06-05

Applicant: RCA CORP

Inventor： HULLS LEONARD ROBIN ,  HADDEN STEPHEN CLOW

IPC: G01L3/24 ,  G01M15/04 ,  G01M15/10 ,  G01P3/36 ,  G01P3/48 ,  G01P15/16 ,  G01N21/06

CPC classification number: G01M15/108 ,  G01L3/24 ,  G01M15/044 ,  G01P3/36 ,  G01P3/4802 ,  G01P15/16

Abstract: The speed in RPM and the condition, of internal combustion engines is determined from the engine exhaust. An engine has x ignitions per second depending on engine speed, has y ignitions per revolution of the crankshaft depending on number of cylinders and whether two-stroke or four-stroke cycle, and has an engine speed in rpm equal to x times the constant 60/y. A light beam is projected from a source through the exhaust gas exiting from the engine to a photodetector to produce an electrical signal having a frequency which varies over a predetermined range determined by the operating speed range of the engine. A band pass filter passes the frequencies in the predetermined range to a phaselocked oscillator. The error signal developed to make the oscillator track the frequency of the signal varies in accordance with engine speed, and is applied to an electrical meter calibrated to indicate engine speed in revolutions per minute. Engine condition is indicated by an elapsed time counter measuring the time taken in an acceleration burst test to accelerate from a low or idle speed to a high or top speed.

Abstract translation: 从发动机排气确定内燃机的转速和条件。 根据发动机转速，发动机每秒可以发出x次点火，根据气缸数量，曲轴每转一次是否有点火，以及二冲程还是四冲程循环，发动机转速等于常数60的x倍 / y。 光束从源极通过从发动机排出的废气投射到光电检测器，以产生频率在由发动机的运行速度范围确定的预定范围内变化的电信号。 带通滤波器将预定范围内的频率通过锁相振荡器。 开发的使振荡器跟踪信号频率的误差信号根据发动机转速而变化，并被应用于校准为指示每分钟转数的发动机转速的电表。 发动机状态由经过的时间计数器指示，测量在从低速或怠速转速到高速或最高速度加速的加速度猝发测试中所花费的时间。