Knock deriving apparatus for internal combustion engines

Patent · Tue Jan 20 04:00:00 EST 1987

OSTI ID:6816886

Iwata, T; Ueda, A

A knock deriving apparatus is described for an internal combustion engine comprising: a knock sensor responsive to vibrations of the engine producing an output signal containing a broad range of frequencies including a frequency component representing knocks in the engine; a first frequency filter means having a bandwidth for passing a predetermined frequency component of the output signal of the knock sensor and producing a first filtered signal containing a range of frequencies which is wider than the frequency component representing knocks and includes frequencies representing engine noise including noise resonance frequencies near the knock frequency component; a second frequency filter means having a narrower bandwidth than and connected to the first frequency filter means for passing the frequency component representing knocks received from the first frequency filter means while blocking frequencies representing engine noise, and producing an output; a comparative reference generator connected directly to receive the first filtered signal of the first frequency filter means for generating a comparative reference signal representing the average of the first filtered signal produced by the first frequency filter means; and a comparator for comparing the outputs of the comparative reference generator and the second frequency filter means to derive the knocks.

• Assignee: Mitsubishi Denki Kabushiki Kaisha
• Patent Number(s): US 4637245
• OSTI ID: 6816886
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
330100* -- Internal Combustion Engines
ANTIKNOCK RATINGS
COMPARATOR CIRCUITS
CONTROL
ELECTRONIC CIRCUITS
ENGINES
FREQUENCY CONTROL
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
KNOCK CONTROL
MECHANICAL VIBRATIONS
NOISE
RESONANCE
SIGNALS