公开(公告)号：EP0654132A1

公开(公告)日：1995-05-24

申请号：EP93904472.0

申请日：1992-09-15

Applicant: NOISE CANCELLATION TECHNOLOGIES, INC.

Inventor： GOSSMAN, William ,  HILDEBRAND, Steve

IPC: F16F7 ,  G10K11

CPC classification number: F16F7/1005 ,  G10K11/178 ,  G10K2210/129 ,  G10K2210/3045 ,  G10K2210/3217

Abstract: An active force cancellation system adapted to contain vibrations in flexible structures which utilizes co-located vibration sensors and counter-vibration devices to offset linear disturbances without setting off sub-structure vibrations.

公开(公告)号：EP0651899A1

公开(公告)日：1995-05-10

申请号：EP92917023.0

申请日：1992-07-14

Applicant: NOISE CANCELLATION TECHNOLOGIES, INC.

Inventor： ZIEGLER, Eldon W. ,  FRIEDLANDER, Paul ,  DENENBERG, Jeffrey N.

IPC: G06F17 ,  H03H21

CPC classification number: H03H21/0012

Abstract: An adaptive canceller filter module having signal sensors and signal filters in a circuit for use with filtered-x algorithms to adapt the coefficients of one of said filters to minimize the measure of the error.

公开(公告)号：EP0580579A1

公开(公告)日：1994-02-02

申请号：EP91920600.0

申请日：1991-04-19

Applicant: NOISE CANCELLATION TECHNOLOGIES, INC.

Inventor： EGHTESADI, Khosrow ,  HOGE, William, John, Joseph

IPC: G10K ,  H04R ,  G10K11 ,  H04R1 ,  H04R25

CPC classification number: H04R1/2842 ,  H04R1/30

Abstract: L'onde acoustique émise à partir de la face avant (UF) de la membrane amplificatrice d'un haut-parleur présente une polarité opposée à celle de l'onde émise à partir de la face arrière (UB). Si l'on associe les signaux directement l'un à l'autre, ils auront tendance à se neutraliser. On utilise un réseau inverseur de phase acoustique (5) pour s'assurer que l'onde arrière est en phase avec l'onde avant, et l'on utilise les signaux associés pour commander l'entrée d'une ligne de transmission (6) de haut-parleur.

公开(公告)号：EP0516705A1

公开(公告)日：1992-12-09

申请号：EP91904982.0

申请日：1991-02-20

Applicant: NOISE CANCELLATION TECHNOLOGIES, INC.

Inventor： ROSS, Colin, Fraser ,  LANGLEY, Andrew, John ,  EATWELL, Graham, Paul

IPC: F01B25 ,  F01N1 ,  F02B27 ,  F02M35

CPC classification number: F01N1/065 ,  F02B27/001 ,  F02M35/1038 ,  F02M35/125 ,  Y02T10/146

Abstract: Un système de commande permet d'améliorer la commande dynamique en continu de la pression dans les sytèmes de sortie et/ou d'entrée (3) d'une machine (1) afin de commander la performance de la machine. Le système comprend un actuateur (4) qui permet de modifier la pression dans le système sélectionné, un capteur (8) de surveillance du fonctionnement de la machine qui génère un signal représentatif du fonctionnement et une unité de commande (5) sensible aux signaux du capteur qui actionne l'actuateur. L'unité de commande ajuste la performance de la machine selon des données prédéterminées afin d'optimiser la performance de la machine. Ces données peuvent être enregistrées en mémoire (table de consultation) ou l'unité de commande peut fonctionner en fonction d'un algorithme. Un deuxième capteur peut être installé pour générer un signal représentatif du bruit produit par les systèmes de sortie et/ou d'entrée afin de générer des signaux qui permettent à l'unité de commande de réduire le bruit généré par la machine en même temps qu'elle améliore la performance de la machine par un signal actif en retour.

公开(公告)号：EP0507829A1

公开(公告)日：1992-10-14

申请号：EP91901848.0

申请日：1990-12-24

Applicant: NOISE CANCELLATION TECHNOLOGIES, INC.

Inventor： ROSS, Colin, Fraser

IPC: G10K11

CPC classification number: G10K11/178 ,  G10K2210/121 ,  G10K2210/125 ,  G10K2210/128 ,  G10K2210/1281 ,  G10K2210/12822 ,  G10K2210/129 ,  G10K2210/3019 ,  G10K2210/3032 ,  G10K2210/511

Abstract: An active vibration reducing system for controlling the vibration generated by a source of periodic or quasi-periodic vibration is characterised in that a weighted sum of the output of at least two sinusoidal waveform generators each synchronised to the frequency of the source of original vibration to generate harmonics of the frequency of the source, is supplied to at least one actuator (5) which generates additional vibration, sensor means (6) is used to monitor the effect of the additional vibration on the original vibration and the weighting of the sum of the outputs is adjusted so that within a defined region the amplitude of the combined vibration is reduced.

公开(公告)号：EP0651899B1

公开(公告)日：2001-02-28

申请号：EP92917023.1

申请日：1992-07-14

Applicant: NOISE CANCELLATION TECHNOLOGIES, INC.

Inventor： ZIEGLER, Eldon W. ,  FRIEDLANDER, Paul ,  DENENBERG, Jeffrey N.

IPC: G06F17/00 ,  H03H21/00

CPC classification number: H03H21/0012

公开(公告)号：EP0694234B1

公开(公告)日：2000-03-29

申请号：EP92914496.2

申请日：1992-06-25

Applicant: NOISE CANCELLATION TECHNOLOGIES, INC.

Inventor： EATWELL, Graham

IPC: H04B15/00 ,  H04B1/10 ,  H03B1/04

CPC classification number: G10K11/178 ,  G10K2210/121 ,  G10K2210/3028 ,  G10K2210/3032 ,  G10K2210/3045

Abstract: A control system for controlling periodic disturbances employing a delay inverse filter (5) for supplying a signal, in response to a disturbance signal received by a sensor (1), a variable delay circuit (6) which is adjusted such that the delay through the delayed inverse filter and the variable delay is equal to a whole number of cycles of the disturbance signal. The output from said variable delay circuit being supplied to an actuator (9) such that it is combined with said disturbance signal at the sensor.

公开(公告)号：EP0655151B1

公开(公告)日：2000-03-22

申请号：EP92920567.2

申请日：1992-09-15

Applicant: NOISE CANCELLATION TECHNOLOGIES, INC.

Inventor： ZIEGLER, Eldon, Jr.

IPC: G06F17/00 ,  H03H21/00

CPC classification number: H03H21/0012 ,  G10K11/178 ,  G10K2210/3011 ,  G10K2210/3019 ,  G10K2210/30232 ,  G10K2210/3042 ,  G10K2210/3046

Abstract: A digital virtual earth (DVE) cancellation system which receives a phenomena input signal via multiple sensors (1, 2, 3) representing residual phenomena to be canceled, and has adaptive filters (12, 24, 25) for each of the multiple sensor/actuator pairs, (1, 4, 2, 5, 3, 6) which generate the appropriate cancellation signal (19, 20, 21) for the associated actuator (4, 5, 6). The multiple interacting DVE (MIDVE) algorithm estimates the noise at each sensor (1, 2, 3) by subtracting out the combined effects of each actuator signal (19, 20, 21) from the residual signal (16, 17, 18) at that sensor (1, 2, 3). This estimated noise signal is used to control the adaptive filters (12, 24, 25) associated with the subject actuator (4, 5, 6). These filters (12, 24, 25) receive the estimated noise as input. They then produce the cancellation signals by filtering the estimated noise with the filter weights. These weights are adapted using the residual signal (16, 17, 18) and the estimated noise convolved with the system impulse responses.

公开(公告)号：EP0705471B1

公开(公告)日：1999-08-18

申请号：EP94921355.7

申请日：1994-06-22

Applicant: NOISE CANCELLATION TECHNOLOGIES, INC.

Inventor： JONES, Owen

IPC: G10K11/16

CPC classification number: G10K11/178 ,  G10K2210/1081 ,  G10K2210/3028 ,  G10K2210/3039 ,  G10K2210/3045

Abstract: The susceptibility of an active noise cancellation system to overloading due to very low frequencies is reduced by subtracting the low frequency components of an applied noise field from the residual signal. Low frequency components of the applied noise field outside the normal range of human hearing are detected by an external sensor and isolated by a filter circuit. The isolated low frequency signal is subtracted from the residual signal, resulting in a modified residual signal with reduced low frequency components. The cancellation system thus eliminates very low frequency cancellation signals, without sacrificing bandwidth or system performance within the audible range.

公开(公告)号：EP0660958B1

公开(公告)日：1999-06-23

申请号：EP92920842.9

申请日：1992-09-21

Applicant: NOISE CANCELLATION TECHNOLOGIES, INC.

Inventor： EATWELL, Graham

IPC: G06J1/00 ,  H03H17/02

CPC classification number: H03H17/0283