Abstract:
A method includes the steps of: detecting “starter ON” by IG-SW signal (step S12); calculating an moving average value TCRKAVE of crank pulse intervals (steps S13-S17); determining engine starting when the TCRKAVE is less than or equal to a threshold value Tth (step S19); and controlling a vibration isolating support unit M based on a natural vibration frequency of the engine when engine starting is determined (steps S20-S22).
Abstract:
In an acoustic control system an operation range of an active type noise control device (an ANC device) and an operation range of an active type effect sound control device (an ASC device) are exchanged in accordance with the number of working cylinders of an engine.
Abstract:
The natural vibration frequency of a roll resonance which does not occur since the engine rotation number is high in a normal operation range of an engine is detected at the time of engine start or stop when the engine rotation number is lower than the normal operation range, and thus the natural vibration frequency of the roil resonance can be detected with a good accuracy. A current is generated by an electromotive force of an actuator of the active vibration isolation support device excited by the engine immediately before stopping its rotation, and the frequency of the current is used to detect the natural vibration frequency of the engine, and the roll resonance of the engine is suppressed by controlling the operation of the active vibration isolation support device at the time of engine start based on the natural vibration frequency, thereby not only eliminating the need of a specific frequency detection sensor, but also effectively reducing the vibration at the time of engine start when the roll resonance becomes strong.
Abstract:
The natural vibration frequency of a roll resonance which does not occur since the engine rotation number is high in a normal operation range of an engine is detected at the time of engine start or stop when the engine rotation number is lower than the normal operation range, and thus the natural vibration frequency of the roil resonance can be detected with a good accuracy. A current is generated by an electromotive force of an actuator of the active vibration isolation support device excited by the engine immediately before stopping its rotation, and the frequency of the current is used to detect the natural vibration frequency of the engine, and the roll resonance of the engine is suppressed by controlling the operation of the active vibration isolation support device at the time of engine start based on the natural vibration frequency, thereby not only eliminating the need of a specific frequency detection sensor, but also effectively reducing the vibration at the time of engine start when the roll resonance becomes strong.
Abstract:
A method includes the steps of: detecting “starter ON” by IG-SW signal (step S12); calculating an moving average value TCRKAVE of crank pulse intervals (steps S13-S17); determining engine starting when the TCRKAVE is less than or equal to a threshold value Tth (step S19); and controlling a vibration isolating support unit M based on a natural vibration frequency of the engine when engine starting is determined (steps S20-S22).
Abstract:
In an acoustic control system an operation range of an active type noise control device (an ANC device) and an operation range of an active type effect sound control device (an ASC device) are exchanged in accordance with the number of working cylinders of an engine.