Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
175 words
An apparatus for detecting of unesirable combustion characteristics in a spark-ignited internal combustion engine, the apparatus including a sensor means for sensing a solid-borne sound signal and for providing an output signal thereof, and a band-pass filter means tuned to an engine knock vibration frequency, the output signal of the sensor means being fed to the by-pass filter means, a rectifier means for rectifying a signal received from the band-pass filter means to an engine knock signal, means for converting the output signal from the sensor means into an engine knock reference signal, and a comparator means for comparing the engine knock signal with the engine knock reference signal and for providing an output signal if the knock signal exceeds the knock reference signal, characterized in that comparing means are provided for receiving the output signal from the comparator means and for providing an output signal of a predetermined time duration if a time duration of the output signal of the comparator means is longer than a specific preset time duration of the comparing means.
Claim 2
Independent Claim
175 words
An apparatus for detecting of unesirable combustion characteristics in a spark-ignited internal combustion engine, the apparatus including a sensor means for sensing a solid-borne sound signal and for providing an output signal thereof, and a band-pass filter means tuned to an engine knock vibration frequency, the output signal of the sensor means being fed to the by-pass filter means, a rectifier means for rectifying a signal received from the band-pass filter means to an engine knock signal, means for converting the output signal from the sensor means into an engine knock reference signal, and a comparator means for comparing the engine knock signal with the engine knock reference signal and for providing an output signal if the knock signal exceeds the knock reference signal, characterized in that comparing means are provided for receiving the output signal from the comparator means and for providing an output signal of a predetermined time duration if a time duration of the output signal of the comparator means is longer than a specific preset time duration of the comparing means.
Claim 3
Dependent Claim
47 words
An apparatus according to claim 1, characterized in that the time duration of the output signal of the comparing means is equal to the difference between the time duration of the output signal of the comparator means minus the specific preset time duration of the comparing means.
Claim 4
Dependent Claim
37 words
An apparatus according to claim 1, characterized in that means are provided for determining the time duration of the output signal from the comparing means and for providing an output control signal to an engine control means.
Claim 5
Dependent Claim
42 words
An apparatus according to claim 3, characterized in that the determining means is a constant frequency oscillator means which enables the time duration of the output signal from the comparing means to be counted out by the oscillations of the oscillator means.
Claim 6
Independent Claim
76 words
An apparatus according to one of claims 2, 3 or 4, characterized in that the converting means includes a band-stop filter means tuned to a frequency of the knock vibration and an r.m.s. rectifier means arranged in series with the band-stop filter means, and in that the output signal of the sensor means is fed to the band-stop filter means and an output signal from the band-stop filter means is fed to the r.m.s. rectifier means.
Claim 7
Dependent Claim
37 words
An apparatus according to claim 5, characterized in that the converting means further includes an amplifier means for amplifying an output signal of the r.m.s. rectifier means and for providing an output signal to the comparator means.
Claim 8
Dependent Claim
53 words
An apparatus according to claim 6, characterized in that an input amplifier means is disposed between the sensor means and the band-pass filter means and band-stop filter means for amplifying the output signal of the sensor means prior to an output signal being fed to the band-pass filter means and band-stop filter means.