Patent application number | Description | Published |
20090028353 | ACTIVE SOUND EFFECT GENERATING APPARATUS - An active sound effect generating apparatus includes a controller (a fourth acoustic adjuster and a fifth acoustic adjuster) which determines the amplitude of a control signal by adjusting the amplitudes of reference signals (intermediate signals) depending on an engine rotational frequency change [Hz/second] calculated by an engine rotational frequency change calculator and an accelerator opening [%] detected by an accelerator opening sensor. | 01-29-2009 |
20090060217 | VEHICULAR ACTIVE VIBRATORY NOISE CONTROL APPARATUS - A vehicular active vibratory noise control apparatus includes an adaptive notch filter (second control signal generating unit) for generating a corrected error signal representative of a road noise only by removing the component of a rotational frequency (the component of an engine muffled sound) from an error signal, generates a first control signal from the corrected error signal and a reference signal, and reduces the component of the rotational frequency (engine muffled sound) at a position where a microphone is located (evaluating point). | 03-05-2009 |
20090067638 | VEHICULAR ACTIVE VIBRATORY NOISE CONTROL APPARATUS - A subtractor subtracts a first control signal output from a first bandpass filter from an error signal, and supplies a differential signal to a second bandpass filter. The second bandpass filter, which has a central frequency of 70 Hz, is affected by an operation of the first bandpass filter, i.e., a first control signal, which has a central frequency of 40 Hz. The first bandpass filter is not affected by an operation of the second bandpass filter, i.e., the second control signal. | 03-12-2009 |
20120189132 | ACTIVE VIBRATION NOISE CONTROL APPARATUS - An active vibration noise control apparatus uses an adaptive control process, which predicts rear road wheel noise canceling sounds by correcting a front road wheel reference signal or a rear road wheel reference signal with a corrective filter, based on different characteristics of front road wheel suspensions and rear road wheel suspensions. | 07-26-2012 |
20130136269 | ACTIVE VIBRATION NOISE CONTROL APPARATUS - An active vibration noise control apparatus cancels out vibration noise generated in the passenger compartment of a vehicle when the vehicle is traveling, by outputting canceling vibration noise. The active vibration noise control apparatus includes a frequency switcher. The frequency switcher calculates a phase angle change between a phase angle in a complex space of a filter coefficient of an adaptive notch filter and a previous phase angle calculated when the filter coefficient is updated previously, and changes a target frequency of a reference signal depending on the calculated phase angle change. | 05-30-2013 |
20130136270 | ACTIVE VIBRATION NOISE CONTROL APPARATUS - An active vibration noise control apparatus is provided. When a vehicle speed changes thereby to change frequency characteristics (peak-amplitude frequency) of vibration noise, the active vibration noise control apparatus refers to a vehicle speed versus frequency correspondence table representing a correspondence relation between a vehicle speed of a vehicle and a frequency of a reference signal, and changes the frequency of the reference signal that is used by an adaptive notch filter. | 05-30-2013 |
20130259249 | ACTIVE VIBRATION NOISE CONTROL APPARATUS - An ANC apparatus using so-called adaptive control is provided with a cancellation sound output means which outputs front wheel cancellation sound that cancels front wheel vibration noise due to front wheel vibration at a position to be silenced on the basis of a front wheel reference signal, and outputs rear wheel cancellation sound that cancels rear wheel vibration noise due to predicted rear wheel vibration at the position to be silenced on the basis of a rear wheel reference signal, and a turning state detection means which detects a turning state of a vehicle. When a difference in travel trajectory between a front wheel and a rear wheel is detected on the basis of the turning state, the cancellation sound output means suppresses the output of the rear wheel cancellation sound. | 10-03-2013 |
20130315409 | ACTIVE NOISE CONTROL APPARATUS - An active noise control apparatus includes a first active noise controller for generating a first canceling signal for a first noise type, a second active noise controller for generating a second canceling signal for a second noise type that is different from the first noise type, a mixer for mixing the first canceling signal and the second canceling signal into a mixed canceling signal, a canceling sound output unit for outputting a canceling sound based on the mixed canceling signal, and an amplitude suppressor for suppressing the amplitude of the second canceling signal depending on the amplitude of the first canceling signal. | 11-28-2013 |
20140286505 | VEHICULAR ACTIVE VIBRATIONAL NOISE CONTROL APPARATUS - A vehicular active vibrational noise control apparatus includes an amplitude limiter for limiting the amplitude of a canceling signal based on a signal level of an audio signal, and a vehicle speed detector for detecting the vehicle speed of a vehicle, which incorporates therein the vehicular active vibrational noise control apparatus. The amplitude limiter changes an amplitude limitation rule, which represents a relationship of a limiting value for the amplitude of the canceling signal to the signal level, depending on the vehicle speed, and limits the amplitude of the canceling signal based on the limiting value determined according to the amplitude limitation rule. | 09-25-2014 |